I am struk with enabling the MSIx in the Guest OS for 82599. In hardware MSIx capability is set it has "70" PF driver is loaded to enable the Virtual function in the host then "lspci" command is used to check whether VF is enabled or not .

VF configuration space for msix "capability [70] MSIx " it is showing correct in the host.

But if i map the VF to Guest OS then it is showing "capability [40] MSIx".SO MSIx is enabled is not detect by the hardware and the VF interrupt is not functioning properly

I asked around about your post and heard back from a few developers. In our labs MSI-X capability is displayed in the correct offset of [70]. We do not know why you are seeing something different. Of course there could be something differentwith QEMU or the guest on your setup.

My SR-IOV Guru's believe this is likely a Fedora 14 problem. We would like to suggest using the latest Fedora release, or try to reproduce the problem with RHEL 6.2.

It takes a several components to make SR-IOV work, BIOS, platform,end-point device (the Intel 82599) and of course the OS. There are lots and lots of patches to the linux kernel for SR-IOV support. Sometimes not all of those patches make it into a distro release due to any number of reasons.

Thanks for trying that and reporting your findings. It would appear to be some kind of DMAR issue - we are preparing to investigate. It makes sense if there is a DMAR problem that VF's assigned to a VM would no work.

To aid in the investigation, our engineers have asked if you are using the inbox (kernel) drivers, or the latest from sourceforge.

I do not know what is happening with this DMAR issue you have described. We suspect it may be a BIOS issue, however I will pass along the information you provided to our SR-IOV experts and relay back anything they may offer by way of explaination.